<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Promise-catch</title>
</head>
<body>
    <script>
        const p = new Promise((resolve,reject)=>{
            setTimeout(()=>{
                reject("出错啦？");
            },1000)
        })

        p.catch(reason=>{
            console.warn(reason);
        });
    </script>
</body>
</html>